Rhododendron plant named ‘HORT01’

ABSTRACT

A new cultivar of  Rhododendron  plant named ‘Hort01’ that is characterized by dark red double flowers with a long life of approximately 30 days, no bracts and a low level of leaf drop.

Botanical classification: Rhododendron simsii.

Variety denomination ‘HORT01’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar ofRhododendron plant botanically known as Rhododendron simsii andhereinafter referred to by the cultivar name ‘Hort01’.

The new cultivar is the product of a breeding program conducted by theinventor in a cultivated area of Kruishoutem, Belgium. The objective ofthe breeding program is to develop new Rhododendron cultivars that havelong lasting flowers and bright green leaves.

‘Hort01’ is a hybrid that originated from the hybridization of thefemale or seed parent a proprietary selection of Rhododendron simsiiidentified as ‘Ambrosiana’ (not patented) and the male or pollen parenta proprietary selection of Rhododendron simsii identified as ‘92138’(not patented). The crossing was conducted in the Spring of 1998. Thecultivar ‘Hort01’ was selected by the inventor in March of 2000 as asingle plant within the progeny of the stated cross in a greenhouseenvironment of Kruishoutem, Belgium.

Asexual reproduction of the new cultivar ‘Hort01’ by cuttings was firstperformed in November of 2000 in Kruishoutem, Belgium. Since that time,under careful observation, the unique characteristics of the newcultivar have been uniform, stable and reproduced true to type insuccessive generations of asexual reproduction.

SUMMARY OF THE INVENTION

The following represent the distinguishing characteristics of the newRhododendron cultivar ‘Hort01’. These traits in combination distinguish‘Hort01’ as a new and distinct cultivar.

-   -   1. Rhododendron ‘Hort01’ exhibits dark red flowers.    -   2. Rhododendron ‘Hort01’ exhibits an absence of bracts.    -   3. Rhododendron ‘Hort01’ exhibits a low level of leaf drop.    -   4. Rhododendron ‘Hort01’ exhibits long lasting flowers.

The closest comparison varieties are Rhododendron ‘Friedhelm Scherrer’(not patented) and ‘Glazer 10’ (not patented).

‘Hort01’ is different from ‘Friedhelm Sherrer’ in having full doubleflowers, no bracts and less leaf drop. The growth habit is morespreading. The leaves of ‘Hort01’ are lighter in color. ‘Hort01’ flowerslater than ‘Friedhelm Scherrer’.

In comparison to the female or seed parent ‘Ambrosiana’, ‘Hort01’differs in having darker red flowers and a later flowering period. Incomparison to the male or pollen parent ‘92138’, ‘Hort01’ differs inhaving a later flowering period and a more compact habit.

‘Hort01’ is different than ‘Glazer 10’ in having full double flowers, nobracts and less leaf drop. The growth habit is more spreading. ‘Hort01’flowers later than ‘Glazer 10’.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying photograph illustrates the distinguishing traits ofRhododendron ‘Hort01’. The plant in the photograph shows an overall viewof a 24 month old plant. The photograph was taken using conventionaltechniques and although colors may appear different from actual colorsdue to light reflectance it is as accurate as possible by conventionalphotographic techniques.

BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed description of the new Rhododendron cultivarnamed ‘Hort01’. Data was collected in Kruishoutem, Belgium from 24 monthold greenhouse grown plants in 1.0 liter containers. The time of yearwas Spring and the average temperature was 22° Centigrade during the dayand 18° Centigrade at night. The light level was 5000 Klux and therewere no photoperiodic treatments. Color determinations are in accordancewith The Royal Horticultural Society Colour Chart 2001 edition, exceptwhere general color terms of ordinary dictionary significance are used.The growing requirements are similar to the species. ‘Hort01’ has notbeen tested under all possible conditions and phenotypic differences maybe observed with variations in environmental, climatic, and culturalconditions, however, without any variance in genotype.

-   Botanical classification: Rhododendron simsii ‘Hort01’.-   Use: Ornamental Perennial Shrub.-   Parentage: ‘Hort01’ is a hybrid of the female or seed parent    Rhododendron simsii ‘Ambrosiana’ and the male or pollen parent a    proprietary selection of Rhododendron simsii identified as ‘92138’    (not patented).-   Vigor: Moderately strong-   Growth rate: Approximately 8 cm. in height and 15 cm. in width per    year.-   Growth habit: Broadly spreading, densely branched.-   Plant shape: Flattened globose.-   Suitable container size: 1.0 liter container.-   Height: Average 22 cm. in height.-   Width: Average 40 cm. in width.-   Hardiness: 0° to 40° C.-   Propagation: Cuttings.-   Time to initiate roots: Approximately 30 days to produce roots on an    initial cutting.-   Time to produce a rooted cutting or liner: Approximately 60 days.-   Root system: Fine and fibrous.-   Stem:    -   -   Branching habit.—Freely branching.        -   Average number of lateral branches.—3.        -   Pinching.—Yes.        -   Lateral branch diameter.—3 mm. in diameter.        -   Lateral branch length.—11 cm. in length.        -   Lateral branch strength.—Moderately weak.        -   Stem color.—185A.        -   Pubescence.—Dense, short.        -   Internode length.—8 mm. between nodes.        -   Shape.—Round.        -   Surface.—Dull.        -   Stem strength.—Moderately weak.-   Foliage:    -   -   Texture.—Dull.        -   Leaf arrangement.—Alternate, clustered towards the top of            the stems.        -   Compound or single.—Single.        -   Quantity of leaves per lateral branch.—22.        -   Leaf shape.—Elliptic.        -   Leaf apex.—Acute.        -   Leaf base.—Acute.        -   Leaf length.—3.6 cm. in length.        -   Leaf width.—1.5 cm. in width.        -   Pubescence.—Absent.        -   Leaf margin.—Entire.        -   Vein pattern.—Pinnate.        -   Young leaf color (upper surface).—137C.        -   Young leaf color (lower surface).—138B.        -   Mature leaf color (upper surface).—138B.        -   Mature leaf color (lower surface).—136B.        -   Vein color (lower surface).—143C.        -   Vein color (upper surface).—143B.        -   Leaf attachment.—Petiolate.        -   Petiole dimensions.—8 mm. in length, slightly flattened            2 mm. in width, 1 mm. in height.        -   Petiole color.—145A.        -   Durability of foliage to stress.—Good.-   Flower:    -   -   Flower arrangement.—Terminal clusters.        -   Inflorescence type.—Open funnel-shaped.        -   Inflorescence dimensions.—7.5 cm. in diameter and 4 cm. in            height.        -   Flowering habit.—Continuously once a year.        -   Quantity of flowers per lateral stem.—Approximately 3.        -   Quantity of flower buds per lateral stem.—Approximately 1 to            5.        -   Quantity of flowers and buds per plant.—Approximately 125.        -   Flowering season.—February to April.        -   Time to flower or response time.—2 to 4 weeks depending on            temperature.        -   Rate of flower opening.—After the first flower of a cluster            has opened, all flowers of that cluster will open in            approximately 14 days.        -   Fragrance.—None.        -   Self-cleaning or persistent.—Persistent.        -   Flower bud length.—9 mm. in length.        -   Flower bud diameter.—7 mm. in diameter.        -   Flower bud shape.—Ovate.        -   Rate of bud opening.—10 days.        -   Flower bud color.—Areas of 143C and 185A.        -   Flower aspect.—Upright.        -   Flower shape.—Funnelform.        -   Flower dimensions.—7.5 cm. in diameter and 4 cm. in height.        -   Flower longevity.—Lasts approximately 30 days on plant.        -   Petal appearance.—Dull, slight velvety.        -   Petal texture.—Glabrous.        -   Petal arrangement.—Funnelform, rosette.        -   Number of petals.—Approximately five in number.        -   Petals fused or unfused.—Fused.        -   Petal shape.—Obovate.        -   Petal margin.—Entire.        -   Petal apex.—Rounded.        -   Petal dimensions.—2.1 cm. in length and 1.8 cm. in width.        -   Petal color when opening (upper side).—53C.        -   Petal color when opening (under side).—53C.        -   Petal color when fully opened (upper side).—53C.        -   Petal color when fully opened (under side).—53C.        -   Petal color fading to.—Not fading.-   Calyx:    -   -   Calyx shape.—Rounded.-   Sepals:    -   -   Sepal appearance.—Dull, pubescent.        -   Number of sepals.—Five in number.        -   Sepals fused or unfused.—Fused.        -   Sepal shape.—Ovate.        -   Sepal apex.—Acute.        -   Sepal margin.—Entire.        -   Sepal color.—53C (upper and lower surfaces).        -   Sepal dimensions.—2 mm. in length and 2 mm. in width.-   Bracts: Absent.-   Reproduction organs:    -   -   Stamen number.—1.        -   Anther shape.—Fused to petals.        -   Pistil number.—1 in number.        -   Pistil dimensions.—2.0 cm. in length.        -   Stigma shape.—Club shaped.        -   Stigma color.—155C.        -   Style length.—1.7 cm.-   Seed: Seed production has not been observed to date.-   Disease and pest resistance: Plants of the new Rhododendron have not    been observed for disease or pest resistance.

1. A new and distinct variety of Rhododendron plant named ‘Hort01’ asdescribed and illustrated.